How to Become a Successful Orbital Welder: Tips, Tricks, and Career Paths

Power Source is the main component of the orbital welding machine. It is where all your programs are stored, settings are changed, and where all your accessories are plugged in to.

Water Coolers are often utilized in fab shops where a large amount of prefabrication is being performed. Liquid cooled weld heads maintain a high duty cycle allowing for high-volume dedicated welding operations with high amperage welds.

Weld Heads come in either open or closed varieties. I have no experience with open weld heads, so I will not go into depth on those. Closed style weld heads come in a variety of sizes, dependent on the size pipe or tubing you will be welding. Weld heads vary in size from 1/4″ to 6″ diameter. Each head has interchangeable collets, allowing the user to swap out collets depending on the size of the material.

Electrode selection and preparation are key to success in orbital welding. Size of the electrode will be depending on the material being used and amperage being ran. Tungsten preparation is key and it is suggested to use a tungsten sharpener or purchase pre-sharpened tungsten. If the electrode becomes dirty or blunt, you need to prep the tungsten once again to reduce arc wander or contaminated weld puddles.

Umbilical Cords extended from the power source to the weld head. They come in a variety of lengths, allowing the user to keep the power source in a central location. Typical umbilical cord lengths range from 25 to 75 feet in length.

Lets start with the cutting of tubing and how to reduce the time spent fitting up tubing. Dependent on the size material you are working on, you only have certain options. Orbital welding of tube can be from tubing sizes ranging from 1/4″ to 6″. Most common practices of cutting tubing would be the utilization of tubing cutters or cutting blocks aka saw guides.

Tubing cutters to be used for stainless steel tubing must have the roller bearing guides built into them. Stainless steel is rather tough on any type of cutting tool, so the specific tubing cutters with roller bearing guides are necessary to prevent “walking”. There are several companies who make these. Some of the brands we prefer are Swagelok, Ridgid, and Imperial. If you click on any of those company names, it’ll take you to the specific roller bearing tubing cutters we are referencing. There are other companies who offer these style tubing cutters, but we have no first hand experience with them.

Cutting Blocks aka Saw Guides are one of, if not the most used tools we use as far as cutting high purity tubing is concerned. The user clamps the cutting block onto the tubing to be cut. Take a bandsaw or other cutting device (bandsaw recommended) and cut through the tubing. Once a cut is made, you will have a rough cut on the tubing. This is NOT your final fit up piece. Please read the next paragraph described Facing Tools. Clean out all shavings created by the cutting tool and dispose properly. If you are working in a clean room or gray space, depends on if this type of cutting tool is allowed. Please ask your supervisor prior to utilizing this cutting tool.

Our preferred vendor for cutting blocks is TechSouth. TechSouth is a vendor of all equipment to do with Orbital Welding. Again, there are other vendors out there who make similar tools, however TechSouth is who we have used in the past and are familiar with there equipment. Click the following link for tube & pipe saw cutting blocks.

Facing Tools are a required tool for the autogenous welding process. There are numerous different styles, but the handheld and bench mounted facing tools are most common. Tri-Tool is a leading vendor when it comes to facing tools and facing tool consumables. Handheld facing tools will be utilized for smaller diameter tubing, while bench mounted are for small to large diameter tubing sizes. A variety of collets are available for either type.

A facing tool uses a drill that has a machined adapter that accepts several different collet sizes. These collet sizes are interchangeable depending on the size tubing you are working with. The facing tool has a cutting head tool bit that rotates at a variable speed, set by the user. The variable speed is a adjusted by the user and is usually in the working range of 100 to 400 rpm. The user will insert the tubing and lock it down in the collet. Once the tubing is secured the user will activate the rotating tool bit and will slowly advance the cutting head towards the tubing. Please read the next section describing the best practices for using a facing tool.

When cutting high purity tubing, the standard practice is to place the saw cut approximately 1/8″ back, give or take, from your actual fit up line. A saw cut will not be 100% square, so this is where the facing tool comes in to play. What I like to do when making my mark on the tubing is to take a saw cut guide and a sharpie. Place the outside of the guide at your mark and trace the line around the complete outside diameter of the tubing. This way, no matter the orientation of the tubing in the facing tool, you can always see your line.

As described in the intro to facing tools, when you start facing the tubing, you advance slowly onto the tube. If you advance too quickly into the tubing, it could bog down the tool and cause the facing tool to stop rotating. While were not worried about damaging the tool per se, we are concerned about damaging the tube that is currently locked in the collet. Ever heard the saying “slow is smooth and smooth is fast”? Well, if not, it definitely pertains to orbital welding and fitting orbital tube. Slowly advance the cutting tool bit until you arrive at the sharpie mark you made. Done!

The cutting tool bits can be very easily damaged and are very expensive. Contractors are not thrilled to hear you went through several cutting tool bits per shift. It indicates you are either not skilled with the tools you are operating or you are going too fast and not taking your time. It’s inevitable that a cutting tool bit will chip or become damaged throughout its life span. To help extend the life of the cutting tool bit and increase the overall quality of the tube facing, there are a couple of tricks to remember.

The cutting tool bit is held on with allen keys that lock it into the facing tool head. If you notice a chip on the tool bit where it makes contact to the tube, adjust it up or down to a good cutting surface of the bit. In the pharmaceutical industry, you are not allowed to have any scratches on the inside of the tubing. When facing tubing, if you notice that the inside of the tubing is getting scratched from the coil, make sure your cutting tool bit is not chipped and or causing that coil to rotate back inside of the tubing.

This may seem like a pretty easy concept, but your knowledge base will have to extend a bit outside of orbital welding for this. Yes, you can tack with the orbital head, however I greatly discourage it.

Tack welding with a tig welding machine is highly encourage. “Skin” tacks or tack welds that do not penetrate the tube is a method all in itself that should be highly encouraged to learn. I’ve worked for shops that make you test in with this process, just so they know you understand the methodology behind it. For individuals, who do not have heli-arc experience I would suggest you practice this method. Fitting tube on the bench is one thing, but when you need to fit a tube in a pipe rack, it’s a whole other story.

When fitting up high purity tubing, the high-lo of the tubing needs to be near perfect. Again, in the autogenous weld process, the two pieces of tubing melt a fuse together. Having a fit up that has a lot of hi-lo is less than ideal and will more than likely end up in concavity in the weld or poor penetration.

This is where tacking clamps come in to play. They fit the tube up perfectly so you have no variance in your hi-lo in the tubing. Highly suggested, but sometimes contractors do not supply these specialty tools. Another way to circumvent this is to weld stainless angle iron to a pair of vice grips or sheet metal vice grips. Make a set for different tube diameters and you won’t have an issue while fitting up tubing.

I wanted to address this before going further into this topic. You NEED to have a proper flow of shielding gas going through your tubing when tacking two pieces of tubing together. If you do not, you will either have sugaring or a visual heat signature on the inside of the tubing, if not both. The tubing will then need to be either reworked or replaced. I can not reiterate this enough. Removal of all oxygen in the inner diameter of the tubing is necessary even when tacking.

If you talk to a more experienced orbital welder, they say they can go by the feel of flow when setting a purge. I’d have to agree and disagree with them as every situation has it’s time and place. Are you in the fab shop making spool pieces? Or, are you in the field, doing tie-ins of pre-fabricated pieces? Are you and one other guy running off the same do-er, or is there a bulk purge line setup that maybe 20 other welders are using at the same time? Situation dictates and not one answer is right or wrong. Use your head and understand the consequences of your actions. If you’re going to be lazy, don’t be upset if you bust that weld. Just saying!

What is a magnahelic? A “mag” as its often referred to, is a pressure differential gauge that reads in inches of water column WC. It indicates the pressure difference between the inside and outside of the system being purged.

When using a mag, you need to adapt it somehow to the tube you are working on. This is where having time in field or a fab shop will help you. Often times, orbital welders will acquire Swagelok style stainless fittings to make purge rigs to better help them in certain scenarios. These Swagelok fittings are compression style fittings and are then secured to the tube you are welding. Often times, tee’s are utilized to have a branch line for your incoming purge line and your magnahelic line. It takes time to acquire these types of purge rigs, so sometime you need to come up with ways to acclimate yourself. Best thing to do is befriend an experienced orbital welder that can help you put a rig together.

Setting a purge is again, the most important thing in the orbital welding process. Your tube needs to be free of all oxygen inside of the line, to help create a contaminant free weld. Not only are you setting the ID (inner diameter) purge, but also establishing an OD (outer diameter) purge inside of the weld head. The collets tightened against the tubing create a good OD purge, but sometimes you may have to make a weld, without the collet being attached. I’ll have more on this later.

Setting your ID purge is as easy as using a tube cap, punching a hole in the cap, and placing a bulkhead SS fitting inside of it. Once the cap is placed over the tubing, please make sure to use electrical tape to secure the cap down to the tubing. The last thing you need, is your purge cap to fly off in the middle of a weld. The purge line is under a considerable amount of pressure, it happens.

If you’re lucky enough to making a weld between two bare pieces of tubing, an exit purge cap is all you need. In the field, this isn’t always the case. For an exit purge cap, take a tubing cap and a leather punch set. Punch a hole in the cap and you’re good to go. Sizing the punch hole does take some time to figure out as everyone has there own preference when it comes to purging techniques. The larger the hole in the exit cap, the higher the pressure you need to run on the purge.

Exit Purge on block valves or other fittings where you may not be able to use a purge cap are very common. It makes you think, but it is a relatively easy process. Using aluminum foil tape across the block valve diaphragm openings will help seal your purged line. An exit hole is needed, preferably at the highest point, to help all oxygen escape from the line. Simply take a knife or other sharp object and puncture the tape to create a large enough opening for the purging gas to escape. Be careful not to scratch or mar any of the surfaces when puncturing the tape in this manner. When doing this, fold back the edges of the tape, so they do not close on themselves once under pressure, causing the purging line pressure to increase.

As stated before, slow is smooth and smooth is fast. Make sure all your connections are tight, taped off, exit holes open, and have proper flow. If you can’t feel the purge gas exiting your tube or orifice, wet your finger and stick it in front of the exit opening. It should feel cold to the touch. If you still don’t feel a solid flow of purging gas, you have a leak somewhere. Stop and re-evaluate your purge immediately! If not, I guarantee you’ll have a cut out.

When performing the orbital welding process, it’s become habit to double or triple check my purge connections. That one time you don’t is the time you forgot to turn the purge gas on. It’s happened to all of us, but one time is enough to learn from your mistakes.

The most common answer here is 4 levels plus a downslope level. It makes common sense, you quarter the tubing into 90 degree quadrants and set up each quarter as its own level. Most pre-set programs will be set up this way.

I prefer to setup my levels the same way but with a slight adjustment. I like creating 92 degree quadrants. The reason for doing this, is so that I have a confirmed overlap at the 360 degree portion of my weld. If you start “tailing” or downslope the weld directly at the 360 degree mark, you could end up not having 100% overlap at the end of the 4th level. Again, this is personal preference.

For smaller tubing, I have even made programs that had up to 8 levels. Some may say this is overkill, sure, but I am now able to lower the amperage where I fell necessary instead of waiting for the 90 degree quadrant. It’s all personal preference and i’d suggest practicing with bead on tube techniques prior to making field tube to tube welds to see if this technique matches your style.

To better understand Hi-Amps vs Background Amps, I like to think of the hi-amps as the melting amperage and the background amps as the solidifying amperage. They both are necessary for the autogenous or “fusion” welding process. This process is also called “pulse” welding. When utilizing pulse styling welding, you are able to better control heat input, reduce the heat effected zone, and increase penetration.

Setting your amps for your hi or peak amperage and background amperage takes time and experience. The time to really dial this in, is in the shop performing bead on tube type welds and inspecting not only the exterior of the weld, but more importantly the inside of the tubing. You are looking for penetration, width of weld bead, ripple length, etc.

If you lack penetration, you need to increase your hi-amp. If your weld bead is too wide, you need to reduce your hi-amps and possibly your background amps. There are a lot of variables since a lot of things come in to play. The best I can do is give you a solid starting point, to help you achieve success.

Step and continuous refer to different modes of operation for the welding machine’s current or power output during the welding process. Both processes will get you to the same point, but they both do it slightly different.

Step welding process is where the welding current is applied in discrete, preset steps or stages. The machine applies higher amperage for short intervals, then pauses or reduces the current before applying more heat again. This gives the weld bead a more “stacked dimes” look.

Continuous welding, on the other hand, involves a constant, steady flow of current throughout the entire welding process. The amperage is kept at a relatively constant level without cycling or interruptions.

I personally utilize the continuous welding method. I think it has an overall better appearance and I have had better success with this method. Again, all personal preference. Always check with your supervision to see if one method is required over another in your certain situation.

Pulse speed in orbital welding refers to the frequency at which the welding machine alternates between high and low current during the pulse welding process. The hi amps provide higher amperage to melt the base material, while the background amps maintains the weld pool and prevents overheating.

The pulse speed is typically measured in pulses per second (Hz) and controls how quickly these changes in current occur. A higher pulse speed results in more frequent heat cycles, while a lower pulse speed provides longer heat intervals.

Adjusting pulse speed allows for precise control over heat input, resulting in smoother welds, better penetration, and maintaining a smaller heat effected zone.

The length of the downslope setting is again based on person preference. I prefer to have a longer “tail” and have the amps trail off slowly. It is visually appealing as well as making sure you are inputting proper amps as you are leaving your final level.

It is not uncommon for my orbital welds to have a 30+ second downslope program that reduces to approximately 5 amps. You also need to make sure to keep a post gas coverage after your downslope for at least 15+ seconds.

As stated before, I am a Union Steamfitter of over 10 years. I have performed as an orbital welder in Pharmaceutical shutdowns and in shop settings. Industrial Welding Services is a signatory contractor with UA Local 486 out of Baltimore and I take pride knowing that the training we provide to our members is top notch.

The UA 18A is the orbital welding certification of all UA Locals. It is obtained by going through a UA certified orbital welding class. While this class does teach the basics, a majority of this skillset will be obtained while in the field, learning from other experienced orbital welders.

The orbital welding community may be relatively small, especially on a local level, but it offers significant opportunities for those with the right skills. This highly specialized field allows for travel across the United States and even abroad, as industries like aerospace, pharmaceuticals, and semi-conductors continue to demand top-tier orbital welders. Orbital welding is considered a specialty skill, making it highly sought after in the welding industry. Contractors often offer above-scale pay rates, knowing the limited pool of skilled orbital welders. For those looking to advance in this field, orbital welding can lead to rewarding career opportunities, both in terms of compensation and travel experiences.